Thread controller device

ABSTRACT

Thread controller devices for incorporation in bobbin winding mechanisms and other strand- or thread-carrying machines where a fast moving strand may be inadvertently caught and seized by a rapidly moving drive belt or gear train, which often develops a charge of static electricity strongly attracting the nearby thread, quickly drawing in large quantities of thread and producing a tangled jam of thread in the drive mechanism of the device before the operator can react to stop the machine. A helical coil spring is arched in an arcuate configuration with the radially innermost portions of the spring turns in contact while the radially outermost portions of the spring turns are angularly separated, creating a fanned array of wedge-shaped apertures with their openings presented laterally toward the endwise-moving strand rapidly passing the device. Inadvertent deflection of the strand from its path of endwise movement deflects the endwise-moving strand into one of the wedge-shaped apertures between the spring turns, producing immediate, automatic halting and breaking of the deflected moving strand, and thus avoiding tangled masses of thread tightly jammed on sheaves and drive belts.

United States Patent 72] Inventor Julius Pararra Bethel, Conn. [211App]. No. 876,691 [22] Filed Nov. 14, 1969 [45] Patented Oct. 19, 1971[73] Assignee William Deitch New Haven, Conn.

a part interest [54] THREAD CONTROLLER DEVICE 7 Claims, 6 Drawing Figs.

[52] US. Cl

[51] Int. Cl B6511 54/00,

[50] Field of Search 242/20, 21,

[5 6] References Cited UNITED STATES PATENTS 840,887 1/1907 Wood...112/252.5 UX 2,261,680 11/1941 Hale 2,583,482 1/1952 Greenberg 2,584,3202/1952 Armenti 2,752,872 7/1956 Meissner, Sr. et a1 112/2525 PrimaryExaminer-Stanley N. Gilreath Attorney-Robert l-l. Ware ABSTRACT: Threadcontroller devices for incorporation in bobbin winding mechanisms andother strandor thread-carrying machines where a fast moving strand maybe inadvertently caught and seized by a rapidly moving drive belt orgear train, which often develops a charge of static electricity stronglyattracting the nearby thread, quickly drawing in large quantities ofthread and producing a tangled jam of thread in the drive mechanism ofthe device before the operator can react to stop the machine. A helicalcoil spring is arched in an arcuate configuration with the radiallyinnermost portions of the spring turns in contact while the radiallyoutermost portions of the spring turns are angularly separated, creatinga fanned array of wedge-shaped apertures with their openings presentedlaterally toward the endwise-moving strand rapidly passing the device.Inadvertent deflection of the strand from its path of endwise movementdeflects the endwise-moving strand into one of the wedge-shapedapertures between the spring turns, producing immediate, automatichalting and breaking of the deflected moving strand, and thus avoidingtangled masses of thread tightly jammed on sheaves and drive belts.

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BACKGROUND OF THE INVENTION Conventional bobbin winding mechanismsemployed on all forms of lock stitch sewing machines utilize anelongated span of thread, drawn by the operator from a supply spoolthrough and over suitable guides or sheaves to be wrapped on a bobbinrotated at high speed. The high-speed drive of these machines iscustomarily produced by an elastic rubber belt, and one or more drivebelts may be employed closely adjacent to the unsupported span of threadbeing wound rapidly on the bobbin. Inadvertent deflection of the threadby the operator or others frequently causes the unsupported span ofthread to touch the racing drive belt. The rapidly moving drive beltoften carries such a deflected runaway" thread with it into the drivemechanism, producing a readily accumulated tangled mass of thread,twisted and jammed around belts, sheaves, shafts and adjacent framestructures of the machine.

The operator's normal reaction time is often insufficient to preventsuch runaway thread jams, and machines are often shut down for manyminutes or hours while skilled maintenance personnel disassemble thedevice and pry or cut off the tangled jam of thread. Lost productiontime and wasted man hours caused by such runaway thread jamssignificantly increase manufacturing cost and consumer prices fortextile products.

Similar tangled runaway jams occur in other types of machines whereunsupported strands of fast moving thread, yarn, or similar strandmaterials pass close to high speed driving mechanisms such as elasticdrive belts.

Thus there exists an important unfilled need for strand-controllingdevices capable of instantaneous severing of a deflected thread orstrand in order to minimize or eliminate such jams by reducing to aninsignificant minimum the length of strand which may be drawn into thedrive mechanism of the machine.

Accordingly, a principal object of the present invention is to minimizeor eliminate jams in strand-handling machines, such as sewing machinebobbin winders.

A further object of the invention is to provide strand-controllingdevices capable of gripping and breaking a deflected unsupported strandin response to its lateral deflection from its predetennined path ofendwise movement.

Another object of the invention is to provide such strand controllerdevices capable of producing immediate and substantially instantaneousseveringof this unsupported strand when it is laterally deflected fromits intended path of endwise movement.

A further object of the invention is to provide thread controllerdevices incorporating an arched helical soil spring, having its turnssplayed to form wedge-shaped spaces between them capable of receiving,seizing and causing prompt breaking of the deflected span of thread.

Other and more specific objects will be apparent from the features,elements, combinations and operating procedures disclosed in thefollowing detailed description and shown in the drawings.

THE DRAWINGS FIG. I is a perspective view of a sewing machine bobbinwinding attachment in its engaged winding mode incorporating a threadcontroller device embodying the present invention;

FIG. 1A is a corresponding perspective view of the same bobbin windingattachment in its disengaged, nonwinding mode, shown partiallydisassembled;

FIG. 2 is a fragmentary top plan view of the thread controller deviceshown in FIG. 1;

FIG. 3 is a slightly enlarged, diagonal elevation view, partially incross section, showing the arched helical coil spring incorporated inthe thread controller device of FIGS. 1 and 2;

FIG. 4 is a greatly enlarged fragmentary elevation view, correspondingto the view of FIG. 3, showing a short thread-engaging portion of thearched helical coil spring of FIG. 3; and

FIG. 5 is a similar, fragmentary, end elevation view of the archedhelical coil spring of FIG. 4.

DESCRIPTION The thread controller devices of the present invention aretypified by the embodiment illustrated in FIG. 1, positioned at the rearof a sewing machine bobbin winding attachment and assembled with therear thread guide sheave support. This thread controller 9 underlies theunsupported, endwise-moving strand of thread spanning the space betweenthe thread guide sheave and the bobbin mounted before the operator onthe bobbin winder at the front of the bobbin winding work station, atthe left side of FIG. 1. As there shown, a bobbin 10 is mounted on apower-driven shaft 11 on which it is rotated at high velocity to achievehigh speed winding of thread on the bobbin 10. A thread 12 beingdelivered for winding on the bobbin is led in a delivery segment 13 froma supply reel above the bobbin winding mechanism (not illustrated in thedrawings) through a suitable guide aperture 14 in a guide sheave support15 and over a tensioning guide sheave 16. The guide sheave is generallyformed as two facing clutch plates biased together by a resilient spring17 mounted on a stud l8 protruding from support 15, to provide a threadgripping clutch or brake device to tension the thread being fed tobobbin 10. The thread loop is inserted to force the two facing clutchplates forming this sheave l6 apart against the resilient bias of thespring 17, and permitting the thread loop to slide between the twoclutch plates where it is tensioned by friction to produce the desiredwinding tension as the thread is wound on bobbin 10.

After passing around tensioning guide sheave 16, the strand of threadtravels endwise along the unsupported span I2 toward the front of thework station, to be wound on bobbin 10. Since the drive belt 19providing driving torque for the bobbin winding attachment and for thesewing machine itself is generally positioned beside the unsupportedthread span [2, inadvertent deflections of this span in the direction ofthe drive belt 19 often result quickly in the costly runaway thread jamsdescribed above.

ARCHED HELICAL COIL SPRING The thread controller of the presentinvention is positioned beside the intended endwise path of theunsupported thread span 12, and between this path and the nearby planeof the drive belt 19 creating the risk of seizing and capturing thethread. As indicated in FIGS. 1 and 2, the preferred embodiments of theinvention incorporate a compressed helical coil spring 21 with tightlycoiled contacting turns. Spring 21 is upwardly convexly arched toresemble the Gateway Arch Monument in St. Louis, Missouri, at roughlysemicircular, upstanding arch. The thread span 12 does not pass throughthe arch of spring 21, but instead passes outside and closely adjacentto the arched helical coil spring 21.

During normal bobbin-winding operations, the path of unsupported threadspan 12 is spaced from the nearest turns of the arched helical coilspring 21 by a substantial distance, on the order of an eighth to aquarter of an inch or more, for example, and the thread controllerspring 21 does not interfere with normal bobbin winding in any way.

Lateral deflection of the unsupported thread span 12 toward the viewerin FIG. I, away from belt 19 and spring 21, may provide slight frictionagainst the near flanges of bobbin 10 or sheave l6, slowing the endwiseadvance of the thread 12, but otherwise has no significant effect on thebobbin-winding operation unless such deflection proceeds to the pointwhere the arriving thread is angularly diverted over the flange of thebobbin.

Inadvertent lateral deflection of the unsupported thread span 12 towardbelt 19 and spring 21, upward in the top view of FIG. 2, constitutes thedeflection creating the serious risk of belt jamming. Accordingly, thethread controller 9 is positioned so that as thread 12 is deflectedtowardspring 21, from path 12 toward the deflected thread path 12A shownin dash lines in FIG. 2, the thread reaches and engages the exposedperiphery of coil spring 21 before it reaches the vicinity of drive belt19.

As shown in the drawings, the spring 21 is held in its upward convexlyarched configuration by the anchoring of its ends on a base plate 22anchored between a bobbin winder base 23 forming the platform for thebobbin winder attachment, and an upstanding guide sheave support 15.These assembled parts are anchored by such means as a screw 24 fittingthrough suitable aligned apertures in guide sheave support 15, baseplate 22 and the bobbin winder base 23.

As indicated in FIGS. 1-3, the forward end of the spring 21, comprisingthe last two or three turns of the spring, is positioned on thediagonally foremost corner of plate 22 closest to thread 23, engaged ina circular aperture 26 in plate 22, having an inside diameter slightlygreater than the outside diameter of spring 21. The edge of aperture 26fits between two adjacent turns of spring 21, which sandwich and gripthe plate 22 between themselves, firmly anchoring the front end ofspring 21 in position on one edge of aperture 26. The diagonallyrearmost end of spring 21 is similarly anchored in position by havingits final few turns threaded through a differently shaped rear anchoringaperture 27, which may be formed as an elongated slot having a widthslightly greater than the wire diameter of the resilient spring wire ofwhich helical coil spring 21 is formed, as shown in the top view of FIG.2.

CONSTRUCTION AND ASSEMBLY The assembly of the thread controller deviceshown in the drawings thus comprise the upright positioning of apredetermined short length of the helical coil spring 21 with its lowerend juxtaposed with slot aperture 27, and the rotative, downward,helical advance of the spring 21 with its lowermost free end beinginserted through slot aperture 27 and being turned to thread this freeend through slot 27 to reach the threaded, installed positionillustrated in FIG. 3. The uppermost end of this predetermined shortlength of helical coil spring is then bent forward to form the uprightarch shown in the drawings, and this free end is then inserted throughthe forward aperture 26 and urged outwardly, away from slot aperture 27,to form the sandwiched-anchoring engagement illustrated in FIG. 3,firmly positioning the helical coil spring 21 in a stiff resilientupstanding arch diagonally positioned beside and close the theunsupported thread span 12.

In the preferred embodiments of the invention, the helical coil spring21 is formed of American Steel Wire (Washburn & Moen or Roebling) Gagenumber 48 spring steel wire 0.0048 inch OD, coiled into a tight helixhaving an outside diameter of approximately 3/8th of an inch. Thepredetermined short length of this helical coil spring employed to formspring 21 is about 2 and 7/8 inches-long, electroplated or hot dippedzinc galvanized spring steel. The preferred dimensions of spring 21 mayof course be varied as desired, and the angular diagonal position of thearched spring 21 relative to the thread span 12 may also be changed ifdesired.

RUNAWAY THREAD CONTROL OPERATION As the thread 12 at position 12A (FIG.4) is deflected further to position 128, as shown in FIG. 4, it enters awedgeshaped space between two adjacent turns of spring 21. Furthersidewise deflection, toward rear aperture 27 and the drive belt 19 to beprotected by the device, causes further descent of the thread toward theposition 12C shown in FIG. 4 and FIG. causing the span of thread to beengaged more deeply in the wedge-shaped space between the spread turnsof spring 21.

As indicated in FIG. 5, as the deflected thread descends deeper betweenthe spring turns into the wedge-shaped aperture therebetween, iteventually reaches a position where the spacing between the turns ofspring 21 is insufficient to permit further inward movement of thethread 12, which thus finds itself in frictional engagement with thefacing surfaces of the spring turns. This frictional engagement producesdrag forces tending to impede the advance of the thread 12, and thesedrag forces are increased with further lateral deflection of the thread,ultimately causing the thread 12 to be seized at a point 12D between twoturns of spring 21 with sufficient tractive drag force to create tensilestress within the thread causing it to break, when this tractive dragopposes the winding tension produced by rotation of bobbin 10 or therunaway tension produced by snagging of the thread on drive belt 19.

If the lateral deflection of the unsupported thread span 12 hasprogressed sufficiently far to bring the thread into contact with belt19, the thread may be drawn rapidly along with belt 19 into its drivesheaves, but the tractive engagement and breaking of the span 12 permitsonly an extremely short length or runaway thread to be drawn along withthe belt 19. The remainder of the thread halts its endwise movement, andthe short thread span 29 between spring 21 and sheave 16 is presented inconvenient position for manipulation by the operator for rethreading afresh span 12 from sheave 16 to shuttle 10. The short length of runawaythread drawn into belt 19 will normally be only a foot or two in length,and has no significant effect upon the drive belts or sheaves in theadjacent drive mechanism of the nearby machinery.

The arched spring 21 presents a large plurality of wedgeshaped aperturesfanned or splayed in an are facing the predetermined path of endwisemovement of the strand 12. When strand 12 is deflected to bring it intoengagement with spring 21, as at path 12A, each of the protrudingrounded peripheries of the intervening spring turns (FIG. 5) providesmooth guide ridges over which strand l2 slides instantly into thenearest wedge-shaped aperture, as at path 128.

In the position illustrated in FIG. 2, with a "rake angle of about 60between the central plane 28 forming the arch plane of the arched spring21 and the thread span 12, the deflected thread, moving toward deflectedpath 12A, reaches its first contact with spring 21 at a point nearer toguide sheave 16 that is the arch plane 28.

The rake angle between spring 21 and thread 12 shown in FIG. 2,producing this first contact of thread 12A with spring 21 at a part ofspring 21 closer to sheave 16 than central arch plane 28, places thepoint 12D of tractive engagement and seizure of the thread between theturns of spring 21 at a point of entry of the advancing thread betweenthe turns of the spring. This provides a fail safe" factor in that asecond point of engagement 12E, shown at the left-hand side of FIG. 5,is also available at a subsequent position along the path of travel ofthe thread 12, where the thread again passes between the turns of spring12 on its exit therefrom. The second seizure point 12E may serve toprovide the required tractive engagement and breaking force on thread 12if the arch of the spring 21 should be rearwardly deflected towardsheave 16 by the operator's hand, for example.

It will be evident from an inspection of FIGS. 1 and 2 that the upwardconvex arch of spring 21 provides a large multiplicity of wedge-shapedgaps between adjacent turns of the spring, all facing directly outwardtoward the various alternative positions of the deflected path 12A ofthe thread. Accordingly, deflections downward, rearward or laterallysidewise toward the belt 19 all move the thread 12 toward the outermostperiphery of spring 21, eventually causing the thread 12 to enter awedgeshaped space between two adjacent turns of the spring 21, in themanner shown in FIG. 4. When spring 21 is arched along a curved axissubstantially coinciding with a circular arc, the resulting evendistribution of distortion along spring 21 produces these similarwedgeshaped apertures arrayed around the entire exposed periphery ofspring 21. If the arch departs notably from a circular arc, one or morestraighter" portions of the spring 21 then fail to provide wedge-shapedapertures because the turns of the spring are not spread apart angularlyover such straight portrons.

The "compressed" arched helical coil springs utilized in the preferredembodiments of the invention exhibit a balance of stiffness andflexibility providing a slight forward flexing capability. This permitsspring 211 to lean or bend toward the bobbin to a flexed position suchas 21A shown in dashed lines in FIG. 2. Such bending is normallyproduced by the tractive friction drag force tensioning the thread as itengages the spring turns at seizure point 121), causing the wedge-shapedspaces between the turns of spring 21 to revolve or roll away fromsheave 16 counterclockwise as viewed in FIG. 5, as the spring deformsflexibly and leans away from sheave 16. As a result, the points ofcloses contact of the spring turns move out of central arch plane 28,revolving counterclockwise toward sheave 16. This produces an eventighter grip of the two spring turns seizing thread 12 at seizure point120, further increasing friction and resulting thread tension to achievethe desired thread-breaking tensile stress promptly and effectively inthread 112.

The simplicity of construction of the thread controller devices of thepresent invention is illustrated by the embodiment shown in thedrawings, where only two additional parts, plate 22 and spring 21, arerequired for fabrication, assembly and insertion between conventionalexisting structures 15 and 23 of a standard bobbin winding assembly. Themanufacturing economy of the assembly of parts 21 and 22 as illustratedin the FIGURES provides a significant advantage over prior art threadcontroller devices such as those shown in U.S. Pat. Nos. 840,887;1,187,071; 2,261,680; 2,752,872 and 2,867,184. Several of these patentsshow helical coil springs surrounding elongated cutter blades used forsevering a span of thread. These prior art devices fail to utilize thetractive frictional engagement of the span of thread between adjacentturns of the spring to provide the thread controlling, guiding, grippingand breaking action of the devices of the present invention. Instead asharpened cutter blade is positioned for engagement with the thread andprovides a far less reliable and far more expensive device forcontrolling deflected thread.

A further advantage of the thread controllers of this invention is theirthread-severing capability. A quick, intentional, manual deflection ofthread 112 into engagement between the turns of spring 21 causes thespring to seize and break the thread. The operator may thus remove thefilled bobbin while the free end of thread 29 is held, convenient forthreading and winding on the next bobbin.

Another advantage of these devices is their combined safely andversatility. No knife blades or sharp cutting edges are employed, butmanual depression of the strand laterally or downward toward spring 21from any angle produces quick, safe and highly effective cuttingoperation, while also gripping and presenting the freshly severedstrand-end for manual withdrawal whenever required.

Loosening of the clamping screw 24 in its thread screwreceiving aperture25 formed at the rear end of base 23 permits lateral adjustment oftension guide sheave 16 to centralize strand 12 on bobbin 10 for evenlydistributed winding thereon. To assure corresponding lateral movement ofspring 21 simultaneously, a lug 29 depending from support 15 is alignedto engage a hole 31 formed in plate 22, and a lateral adjustment slot 32formed in plate 22 receives screw 24 as its protrudes downward through acorresponding aligned lateral adjustment slot 33 formed in support 15.Support 15 and plate 22 may thus be moved together laterally, guided bytheir adjustment slots and by a downtumed rear flange 33 of plate 22embracing the rear edge of base 23. Pivoting movement of plate 22 isthus substantially eliminated, avoiding inadvertent engagement of thearched thread controller spring 21 with the adjusted strand 12 until thestrand is deflected toward the spring.

The devices of the present invention are primarily useful with bobbinwinding attachments of lockstitch sewing machines but similar textilemachines incorporating an unsupported span of yarn or thread passingclose to a high speed drive device such as a belt or a gear train maylikewise be protected by the devices of the present invention, merelyrequiring that the arched spring 21 should be mounted beside andconvexly bowed toward the normal path of endwise travel of thepnsuplported span.

Since e foregoing description and drawings are merely illustrative, thescope of the invention has been broadly stated herein and it should beliberally interpreted so as to obtain the benefit of all equivalents towhich the invention is fairly entitled.

What is claimed is:

1. In a sewing machine bobbin winder incorporating a strand guide sheaveand a bobbin drive shaft carrying a drive sheave engageable with anadjacent exposed sewing machine drive belt, the improvement comprising astrand-controlling device for engaging and breaking a strand travelinginendwise movement through a strand zone from said guide sheave to abobbin on said bobbin drive shaft past said exposed drive beltcomprising a convexly arcuate controller interposed adjacent to saidstrand zone and between said zone and said exposed drive belt with itsoutermost periphery formed into a plurality of fanned wedge-shapedapertures.

A. having their innennost ends narrower than the diameter of theunsupported strand, and

B. having their outermost ends opening outward toward the vicinity ofthe adjacent strand zone and arrayed in an are spaced closely adjacentto the strand zone in an arch plane transversely intersecting the strandzone,

whereby deflected lateral movement of the endwise moving strand towardthe arcuate controller and into interfering engagement therewith bringsthe deflected strand into one of the wedge-shaped apertures and intojamming engagement with the controller at the narrow end of said oneaperture, automatically breaking the strand and preventing the catchingand tangling of the strand in said exposed drive belt.

2. The device defined in claim 1 wherein the arcuate strand controlleris formed as a helical coil spring attached in the arch plane closelyadjacent to the predetermined strand zone.

3. The device defined in claim 2 wherein the arched spring has both ofits ends secured to a support plate anchored to a portion of said bobbinwinder near said strand guide sheave.

4. The device defined in claim 3 wherein the support plate is a thin,rigid plate provided with a pair of spring end-engaging apertures, afirst aperture having its narrowest dimension greater than the wirediameter of the wire coiled to form the spring for threaded engagementwith a first free end of the spring therein, and a second aperturehaving its minimum dimension greater than the outside diameter of thespring itself for receiving the second opposite free end of the springinserted therethrough for sandwiching engagement of the aperture rimbetween two adjacent spring turns near the springs second free end.

5. The device defined in claim 2 wherein the arched helical coil springis resiliently deformable by strand tensile force and by manual forceexerted by an operator.

6. The device defined in claim 2 wherein the helical coil spring isarched along a curved axis substantially coinciding with an arc of acircle.

7. The device defined in claim 5, wherein said strand guide sheave ismounted on the support plate.

1. In a sewing machine bobbin winder incorporating a strand guide sheaveand a bobbin drive shaft carrying a drive sheave engageable with anadjacent exposed sewing machine drive belt, the improvement comprising astrand-controlling device for engaging and breaking a strand travelingin endwise movement through a strand zone from said guide sheave to abobbin on said bobbin drive shaft past said exposed drive beltcomprising a convexly arcuate controller interposed adjacent to saidstrand zone and between said zone and said exposed drive belt with itsoutermost periphery formed into a plurality of fanned wedgeshapedapertures. A. having their innermost ends narrower than the diameter ofthe unsupported strand, and B. having their outermost ends openingoutward toward the vicinity of the adjacent strand zone and arrayed inan arc spaced closely adjacent to the strand zone in an arch planetransversely intersecting the strand zone, whereby deflected lateralmovement of the endwise moving strand toward the arcuate controller andinto interfering engagement therewith brings the deflected strand intoone of the wedgeshaped apertures and into jamming engagement with thecontroller at the narrow end of said one aperture, automaticallybreaking the strand and preventing the catching and tangling of thestrand in said exposed drive belt.
 2. The device defined in claim 1wherein the arcuate strand controller is formed as a helical coil springattached in the arch plane closely adjacent to the predetermined strandzone.
 3. The device defined in claim 2 wherein the arched spring hasboth of its ends secured to a support plate anchored to a portion ofsaid bobbin winder near said strand guide sheave.
 4. The device definedin claim 3 wherein the support plate is a thin, rigid plate providedwith a pair of spring end-engaging apertures, a first aperture havingits narrowest dimension greater than the wire diameter of the wirecoiled to form the spring for threaded engagement with a first free endof the spring therein, and a second aperture having its minimumdimension greater than the outside diameter of the spring itself forreceiving the second opposite free end of the spring insertedtherethrough for sandwiching engagement of the aperture rim between twoadjacent spring turns near the spring''s second free end.
 5. The devicedefined in claim 2 wherein the arched helical coil spring is resilientlydeformable by strand tensile force and by manual force exerted by anoperator.
 6. The device defined in claim 2 wherein the helical coilspring is arched along a curved axis substantially coinciding with anarc of a circle.
 7. The device defined in claim 5, wherein said strandguide sheave is mounted on the support plate.